#include <stdio.h>
#include <string.h>


int main()
{
    char s1[32] = {"123456\0a78910"};
    char s2[] = {"12"};
    //char *p = strcat(s1+2,s2+3);

    //printf("%p %p %p\n", s1, s2, p);
    char*p = strncat(s1,s2,6);
    printf("p  = %s\n", p);
    for(int i = 0; i < 32; i++)
    {
        printf(".%c", s1[i]);
    }
    printf("\n");
}